81107367867811 has 4 divisors (see below), whose sum is σ = 85878389507112. Its totient is φ = 76336346228512.

The previous prime is 81107367867769. The next prime is 81107367867829. The reversal of 81107367867811 is 11876876370118.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81107367867811 - 2⁷ = 81107367867683 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81104367867811) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2385510819625 + ... + 2385510819658.

It is an arithmetic number, because the mean of its divisors is an integer number (21469597376778).

Almost surely, 2^{81107367867811} is an apocalyptic number.

81107367867811 is a deficient number, since it is larger than the sum of its proper divisors (4771021639301).

81107367867811 is a wasteful number, since it uses less digits than its factorization.

81107367867811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4771021639300.

The product of its (nonzero) digits is 18966528, while the sum is 64.

The spelling of 81107367867811 in words is "eighty-one trillion, one hundred seven billion, three hundred sixty-seven million, eight hundred sixty-seven thousand, eight hundred eleven".